Machine and method for forming disposable paper pallets



H. H. NORQUIST ETAL 2,856,826 MACHINE AND METHOD FOR FORMING DISPOSABLEPAPER PALLETS Filed April 19. 1957 15 Sheets-Sheet 1 SQ w R N UNW Oct.21, 1958 H. H. NORQUIST ET AL 2,856,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS Filed April 19,1957 15 Sheets-Sheet 2 Oct-21, 1958 H. H. NORQUIST ETAL 2,856,825

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS 15 Sheeis-Shet 3Filed April 19, 1957 NORQUIST ET AL MACHINE; AND METHOD FOR FORMINGDISPOSABLE PAPER PALLETS Oct. 21, 1958 15 Sheets-Sheet 4 Filed April 19,1957 Oct. 21, 1958 H. H; NORQUIST ETAL 2,356,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS Filed April 19,1957 l5 Sheets-Sheet 5 Oct. 21, 1958 H. H. NORQUIST ETAL 2,355,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS 15 Sheets-Sheet6 Filed April 19, 1957 Q HI N 3w \Q @N RN m H. H. NORQUIST ETAL MACHINEAND METHOD FOR FORMING Oct. 21, 1958 2,856,826

I DISPOSABLE PAPER PALLETS l5 Sheets-Sheet 7 Filed April 19, 1957 15Sheets-Sheet 8 NORQUIST El" AL QN MW H. MACHINE AND METHOD FOR FORMINGDISPOSABLE PAPER PALLETS 0 o o o 0 o O O kn? & wk

Oct. 21, 1958 Filed April 19. 1957' Oct. 21, 1958 H. H. NORQUIST ETAL2,856,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS Filed April 19,1957 15 Sheets-Sheet 9 Oct. 21, 1958 H. H. NORQUIST ETAL 2,856,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS l5 Sheets-Sheet10 Filed April 19, 1957 Oct. 21, 1958 H. H. NORQUIST ETAL 2,856,826MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS Filed April 19,1957 15 Sheets-Sheet 11 INVENTORS, By Harry /9. 6/7fi6/f/ .A a mi Oct.21, 1958 H. H. NORQUIST ET AL 2,356,826

I MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS Filed April19, 1957 15 Sheets-Sheet 12 n v 184K /7/ agwez Oct. 21, 195% H. H.NORQUIST ET AL 2,855,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PALLETS l5 Sheets-Sheet15 Filed April 19, 1957 WHPWWl Mm 11v VEN TOR5. #007 1 7. /2 0/'7z//5/lliilllllli Oct. 21, 1958 H. H. NORQUIST ETAL 2,856,826 MACHINE ANDMETHOD FOR FORMING DISPOSABLE PAPER PALLETS Filed April 19, 1957 15Sheets-Sheet'l4 Oct. 21, 1958 H. H. NORQUIST ETAL 2,356,826

MACHINE AND METHOD FOR FORMING DISPOSABLE PAPER PAL-LETS 15 Sheets-Sheet15 Filed April 19, 1957 Hm m mm AM: g

wmw Q United States Patent 2,856,826 Patented Oct. 21, 1958 lice MACHINEAND METHOD FOR FORMING DISPOSABLE PAPER PALLETS Harry H. Norquist,Hickory Corners, chine Company,

Kalamazoo, and Harry A. Gilbert, M1cl1., assignors to Martinson Ma-Kalamazoo, Mich.

This invention relates to improvements in machine and method for formingdisposable paper pallets. Disposable paper pallets are defined asplatforms formed of corrugated paper and suitably reinforced to supportpiles of cartons or other articles for handling as a unit. The palletsare designated as disposable in that they can be manufactured and used asingle time and discarded at less expense than would be involved inusing a wood or metal pallet and returning the pallet for a second use.The principal objects of this invention are:

First, to provide a machine which will successively bend a prescoredcorrugated bottom panel into a plurality of hollow U-shaped legsconnected at the upper edges by coplaner surfaces and then inserthorizontally zigzag reinforcing fillers into the U-shaped legs andfinally secure a continuous top panel of corrugated paper over the topsof the bottom panel and the zigzag fillers.

Second, to provide a machine having the foregoing properties which caneasily be adjusted to form pallets having different spacing between theU-shaped legs and legs of different widths.

Third, to provide a machine for distributing narrow strips of corrugatedpaper to the U-shaped legs of a bottom panel and folding the strips intozigzag form for insertion into the legs.

Fourth, to provide a mechanical drive including operating and controlcams for actuating the conveyor and panel folding elements of themachine in timed relation.

Fifth, to provide means for forming anchors for the ends of zigzagstrips within the U-shaped legs of the bottom panel of the pallet.

Sixth, to provide a novel method of forming a pallet in which a bottompanel is folded into spaced and connected U-shaped legs and reinforcingstrips are folded into zigzag form and inserted into the hollow legs andretained at the ends after which a top panel is secured across the topsof the bottom panel and reinforcing strips to prevent the bottom paneland its U-shaped legs from opening laterally from their foldedpositions.

Other objects and advantages of the invention will be apparent from aconsideration of the following description and claims. The drawings, ofwhich there are 15 sheets, illustrate a highly practical form of themachine for forming the pallets and the steps involved in the method offorming the pallet.

Fig. 1 is a side elevational view, broken into two consecutive sections,illustrating the general arrangements,

of the machine.

Fig. 2 is a fragmentary top plan view of the bottom panel formingstation of the machine.

Fig. 3 is a fragmentary end elevational view of the bottom panel formingapparatus and station of the machine.

Fig. 4 is a perspective view of the bottom panel of the pallet as it isformed by the mechanism shown in Fig. 3.

Fig. 5 is a fragmentary transverse cross-sectional view through thebottom panel forming mechanism taken along the plane of the line 55 inFig. v2 and showing the mechanism and a bottom panel in unfoldedstarting position. An intermediate position of the bottom panel duringthe folding operation is indicated by the dotted lines.

Fig. 6 is a fragmentary transverse cross-sectional view showing thestructure in Fig. 5 in further actuated bottom panel folding position.

Fig. 7 is-a fragmentary top plan view of the reinforcing filler feedingand inserting section of the machine. Portions of the upper parts of thestructure are broken away to illustrate lower parts.

Fig. 8 is a fragmentary side elevational view of the reinforcing fillerfeeding and inserting portion of the machine appearing in Figs. 1 and 7.

Fig. 9 is a fragmentary vertical transverse cross-sectional view throughthe reinforcing panel feeding and inserting mechanism taken along theplane of the line 9--9 in Fig. 8.

Fig. 10 is a fragmentary top plan view taken along the general plane ofthe line ltll0 in Fig. 9 illustrating the reinforcing and insertingmechanism in partially actuated zigzag forming position.

Fig. 11 is a fragmentary side elevational view of the structure shown inFig. 10 with portions of the bottom panel and bottom panel holdingmechanism broken away to illustrate the position of the zigzagreinforcing panel.

Fig. 12 is an enlarged fragmentary transverse crosssectional view takenalong the plane of the line 99 in Fig. 8 and illustrating in greaterdetail the reinforcing panel inserting mechanism in fully actuatedposition.

Fig. 13 is an enlarged fragmentary side elevational view of thereinforcing panel feed and control mechanism illustrated in endelevation in Fig. 12.

Fig. 14 is an enlarged fragmentary horizontal plan view, partiallybroken away in cross-section, of the reinforcing panel inserting stationillustrating the structure for locating and anchoring the ends of thezigzag reinforcing panel in the hollow legs of the bottom panel of thepallet.

Fig. 15 is a fragmentary vertical cross-sectional view taken along theplane of the lines 15-15 in Figs. 14 and 16 and illustrating theabutment forming mechanism in retracted position.

Fig. 16 is an enlarged fragmentary side elevational view of thestructure for forming the zigzag panel abutments in the bottom panel.

Fig. 17 is an enlarged fragmentary transverse vertical cross-sectionalview through the top panel feeding and attaching section of the machinetaken along the plane of the lines 17-17 in Figs. 1 and 18.

Fig. 18 is an enlarged top plan view of the top panel feeding mechanismshown in Fig. 17 with. the top panel attaching press broken away alongthe plane of the lines 13-18 in Fig. 17.

Fig. 19 is an enlarged fragmentary transverse vertical cross-sectionalview showing the top panel attaching mechanism in fully actuatedposition for connecting the flat top panel to the folded bottom paneland zigzag reinforcing panels.

Fig. 20 is a perspective view of the completed disposable pallet withportions broken away'to illustrate the internal reinforcing elementsthereof.

Fig. 21 is a fragmentary transverse cross-sectional view taken along theplane of the line 21-21 in Figs. 18 and 24 and showing the edge of thetop panel attaching mechanism in fully actuated position.

Fig. 22 is a plan view of the trailing end of the pallet conveyor at thetop panel attaching station showing the drive connections to theconveyor and the structure for laterally adjusting the conveyor,structure for attaching the top panel being omitted.

Fig. 23 is a fragmentary vertical longitudinal crosssectional view takenalong the plane of the line 23-23 in Fig. 3 and showing the structurefor adjusting the spacing at the front end of the machine.

Fig. 24 is a fragmentary transverse vertical cross-sectional view takenalong the plane of the line 24-24 in Fig. -18.

Fig. 25 is a fragmentary transverse vertical cross-sectional view takenalong the plane of the line 2525 in Figs. 1, 7 and 8 showing theoperating cams for the reinforcing panel folding and insertingmechanism.

The pallet which is formed by the machine and method of the invention ismade up entirely of heavy corrugated paperboard of suitable weight. Thepallet itself is more clearly illustrated in Figs. 4 and 20 which showthe pallet to -be made up of an integral bottom panel 38 that isprescore d longitudinally and folded into depending side legs 31 and acenter leg-32 of upwardly opening rectangular U-shaped cross-section.Desirably the inner corrugations within the panel itself extend trans-'v'ersely of the panel 'as shown at 33 in Fig. 4 so that the foldsforming the legs 31 and 32 extend transversely across the corrugation ofthe panel. The upper edges of the legs 31 and 32 are connected by flattop surfaces 34 that determinethe spacing between the legs. Lateralmarginal flanges 35 are left on the outer edges of the outer legs and inthe completed pallet these flanges are folded into 'coplaner relationwith the connecting top surfaces 34.

The interiors of the hollow legs 31 and 32 are reinforced by zigzagreinforcing panels 36 that are arranged vertically on edge and foldedinto horizontal zigzag reaches extending between the opposed side wallsof the legs. The

open tops of the hollow legs are closed by a continuous flat top panel37 secured as by gluing to the tops of the connecting surfaces 34 andthe marginal flanges 35 and to the upper edges of the zigzag reinforcingpanels 36. The longitudinal ends of the zigzag panels 36 are retainedlongitudinally within the hollow legs by ears 33 struck inwardly fromthe sides of the legs. Desirably but not necessarily the vertical heightof the zigzag panels 36 is slightly greater than the depth of the hollowlegs 31 and 32 so that when the top panel 37 is pressed down upon thebottom panel the upper edges of the reinforcing panels 36 are slightlycompressed and deformed as appears at 36A in Fig. 19. As thus describedthe pallet is surprisingly strong and capable of supporting relativelylarge vertical loads so that fork trucks can be used to handle loads byinserting the forks of the truck between the legs 31 and 32. Because ofthe ease with which the pallet can be formed with the machine and methoddescribed the cost of the pallet is sufiiciently low to permit it to bediscarded after a single use.

GENERAL ARRANGEMENT OF THE PALLET FORMING MACHINE tion 40 the details ofwhich appear most clearly in Figs. 2 to 6. From the bottom panel foldingstation 40 thefolded bottom panels are delivered to the zigzagreinforcing panel feeding and inserting station 41. The details of thisstation are disclosed in greater detail in Figs. 7 to 16 and 25. Fromthe zigzag forming and inserting station the partially completed palletsare advanced through'an idler station 42 to the top panel attaching"station 43. The details of the top panel attaching sta- -tion appear inFigs. 17 to 22 and 24. When the speed at which the machine is to beoperated is slow enough to permit setting of the glued connections atthe top panel attaching station 43 this will complete the "machine.However, when the speed of operation of the machine does not providesufficient drying time in the attaching station 43 an additional holdingstation 44 in the form of a supporting conveyor 45 and top panel holdingconveyor 46 may be added to hold the'top and bottom panels togetherwhile the glued connections set.

The several portions and operating elements of the machine are supportedby a suitable framework which will be referred to generally by thereference numeral .470. it will be appreciated that various forms ofsupporting and connecting structures may be devised to support theoperating elements of the machine. The pallets and the initial bottompanels 3% on which they are formed are conveyed continuously through themachine in a step by step fashion by a feed conveyor 47 consisting oftwo transversely spaced link chains supported by suitable rails 43.After the bottompanel has been folded toform the hollow legs 31 and 32,additional conveyor chains '49 supported by rails Stl are provided toassist in supporting and advancing the pallets. The feed conveyor 47 istrained over idler sprockets '51 at the inlet end of the machine and isdriven by drive sprockets 52 at the discharge end of the machine. Thelower conveyor chains 49 that support the bottoms of the legs aretrained over idler sprockets 53 located under the middle of thereceiving section 39 (see Figs. 1, 22, and 23) and extend longitudinallythrough the machine to drive sprockets 54 at the discharge end of themachine. In passing through the toppanel attaching station 43, the lowerreaches of the chains 47 and 49 are trained downwardly as at 490 in Fig.1 to clear the supports that support the pallet'against the pressure ofthe top panel press.

Drive connections The main power source and drive connections of themachine consist of a motor 55 mounted under the rein forcing panelinserting station 41 and connected to a speed reduction transmission 56(see Figs. 1, 7 and 8). The transmission 56 has a first power take-offshaft 57 projecting transversely of the machine and connected by thechain 58 to a transverse shaft 59 carrying the gear 66. The shaft 59drives the reinforcing panel folding mechanism as will be described ingreater detail presently. A longitudinally extending output shaft 61 ofthe transmission drives a first gear and chain 62 with the chainextending upwardly to drive the reinforcing panel distributing andfeeding mechanism as will be described. At the forward side of thetransmission the shaft of drives a transversely extending chain 63 (seeFigs. 7 and 8) that is trained around a sprocket on the longitudinallyextending distribution shaft 64. The shaft 64 is chain connected as at65 to a longitudinal shaft 66 having cams thereon for'actuating variousparts of the machine as willappear presently. The transmission shaft 61also drives a chain 611 to a conveyor drive shaft 612 (see Figs. 1, 7and'S). A transverse cross shaft 67 located at the rear of the insertingstation 41 and under the idler station 42 is driven from the shaft 612and in turn drives a chain 63 extending rearwardly to a sprocket 69(see-Fig. 22) on the rear drive shaft-7t). A clutch-71drivingly.connects the sprocket to the drive shaft for operating thepreviously described sprockets52 and 54 and the con veyor chains 47 and43.

Bottom panel folding station 40 The construction and operation of thebottom panel folding station is disclosed more clearly inFigs. 2 to 6and 23. The flat bottom panels indicated by. the reference character 3%and prescored longitudinally as at 72 are advanced into the foldingstation 40 where they are supported by the chains 47. Located laterallyoutwardly from the chains 47 are two longitudinal backing rails73.

.laterally beyond the sides of the rail. jecting above the pressure railat each end thereof are "of the machine by pivots 102.

side of the machine.

time being the backing rails 73 will be considered as stationary.

At each end of the folding station the cross beams 76 are provided withupstanding brackets 77 rotatably supporting stub shaft 78 on whichmeshing gears 79 are mounted in the transverse center of the machinebetween the backing rails 73. The shafts 78 carry longitudinallyextending folding plates 80 that are thus swingable or rotatable aboutlongitudinal axis to swing between the outwardly inclined portion shownin Fig. and the upwardly extending parallel portion shown in Figs. 3 and6. The plates 80 have wooden facing strips 81 bolted thereto which canbe removed to increase the effective spacing between the folding plates.One of the plates 80 has a crank arm 83 connec ed thereto (see Figs. 2and 3) and depending therebelow for connection to a transverselyextending push rod 84. The outer end of the push rod 84 is connected toa lever 85 pivotally supported at its lower end on a pivot shaft 86 onthe left side of the machine as appears in Figs. 2 and 3. The lever 85carries a cam follower (not illustrated) engagable with the cam 88 on acam shaft 89 extending longitudinally along the left side of themachine. Rotation of the cam shaft 89 and cam 88 thus function tooscillate the meshing gears 79 and swing the folding plates 80 betweentheir advanced folding position and retracted open posrtlon.

Positioned in the approximate center of the folding station 40 is anupright air cylinder 90 having a piston 91 therein yieldably supportedby a spring 92 (see Fig. 3) and air pressure in the cylinder. The spring92 normally supports its piston and the piston rod 93 carried thereby inelevated position directly under the center of the bottom panel 30. Atop pressure rail 94 of rectangular cross-section is supportedlongitudinally above a longitudinal shoe 95 on the piston rod 93 inopposed relation thereto. The pressure rail 94 can be changed in widthby having the wooden facing plates 81 bolted thereto as indicated by thedotted lines 81A in Fig. 5 when the facing plates are removed from thefolding plates 80. The pressure rail 94 has a top plate as that projectsHangers 97 propivotally connected to levers 98 extending laterally tothe right side of the machine. The levers98 are pivotally supported at99 and connected at their outer ends to depending pull rods 1th The pullrods 109 extend downwardly to levers 101 supported at the right side Thelevers 101 have cam followers 103 engaged with cam wheels 103A on alongitudinal cam shaft 104 extending along the right Rotation of the camshaft ltld thus functions to raise and lower the pressure rail 94 andwhen lowered the pressure rail presses the center of the bottom panelagainst the backing shoe 95 on the .yielda'bly supported piston rod 93and depresses the .pressure rail and shoe as shown in Fig. 6. In sodoing the bottom panel is bowed downwardly as indicated bythe dottedlines at 30A in Fig. 5. After the pressure rail 94 is fully depressedthe side folding plates 80 are swung upwardly and inwardly to fold thesides of the center leg 32 of the panel against the sides of thepressure rail 94. The overhanging edges of the top plate 96 of thepressure rail form sharp right angle bends or folds at the upper edgesof the center leg as is shown in Fig. 6.

thereon, thepiston 91 has a sealed sliding fit in the cylin- 6 der 91)to draw air into the top of the cylinder through a valve 87. The pistonrod has a packed sliding fit (not illustrated) in the upper end of thecylinder. The valve 537 is actuated by a push rod 871 extending from thecylinder to the left side of the machine where it is connected to alever 872 (see Fig. 2). The lever 872 carries a follower 8'73 engagedwith a cam 881 on the shaft The cam 881 is contoured to hold the valve87 closed until after the bottom panel 30 is fully formed and has beenadvanced on to the reinforcing panel inserting station 41. The valve 87is then opened to let air escape from thetop of the cylinder so that thespring 92 raises the shoe to support the next succeeding panel 30 forfolding.

Positioned above the cross beams 76 at each end of the folding station41 are upper cross beams 105. The cross beams 1115 have slideways 106adjustably supporting bearing blocks 107. The bearing blocks 107rotatably support cranks 108 slightly above and laterally inwardly fromthe upper edges of the backing plates 73 (see Fig. 5'). The outwardlyand downwardly facing surfaces of the cranks 108 support upper foldingplates 109 of angular cross-section that are thus swingable downwardlyinto opposed relation to the angled backing lates '73. At the front endof the folding station as appears in Fig. 3 the cranks that support theupper folding plates are provided with actuating levers 110 connected tolaterally extending push rods 111. The push rods 111 are connected attheir outer ends to upright levers 112 pivotally supported at theirlower ends on the pivot shafts 36. The levers 112 carry followers 113engaged with box cams 114 on the ends of the previously described camshafts 89 and 104. Rotation of the cam shafts $9 and 104 thus functionsto swing the upper folding plates 1ll9 downwardly and fold down thelaterally inner side walls of the outer legs 31 of the bottom center theplates 117 have crank arms 117A pivotally connected to push rods 118extending laterally outwardly to upstanding levers 119 on the pivotshafts 86. The levers 119 have cam followers engaged with cams 120 onthe cam shafts 89 and 104 so that the side folding plates are swungupwardly to fold up the outer sides of the side legs 31. The marginalflanges 35 of the pallet bottom panel are left standing erect but thepanel is partially broken at the score line of the marginal flanges byreason of being drawn outwardly underneath longitudinally extending holddown plates 121 (see Figs. 2 and 3) supported over the side edges of thebottom panel by the support bars 122 connected to the sides of theframework. The folded bottom panel is then ready to be advanced to thereinforcing panel inserting station 41.

Drive and adjustment connections of the bottom panel forming station Thecam shafts 89 and 104 which actuate the several folding elements at thefolding station are driven from the previously described distributorshaft 64 by laterally extending chain loops 123 (see Fig. 3) trainedaround sprockets on the distributor shaft and the cam shafts. Rotationof the cam shafts is continuous during the operation of the machine andthe angular spacing and configuration of the several cams is adjusted toprovide the proper operating sequence of the several folding elements.

The width of the center leg 32 of the pallet can be changed aspreviously described by removing or chang- I ingthe position of thewooden face plates 81 from the center folding plates to the sides of thepressure shoe 94. In order to adjust the machine for a wider pallet theslides 74 that support the backing plates 73 are moved radiallyoutwardly by rotation of laterally extending screw shafts .124, (seeFigs. 3, and 23). The shafts extend laterally to thesides of the machineand there is a pair of shafts at the front and back of the foldingstation. Chain loops125 are trained around sprockets on the ends of thescrew shafts so that all shafts can be adjusted simultaneously.

The bearing brackets 115 which support the side folding-plates 117 alsomust be adjusted to change the width of the leg sections formed and tothis end the bearing brackets1-15 are slidably mounted on the slides 74and are adjustable with respect thereto by laterally extending screwshafts 126. The screw shafts 126 extend part Way out: toward. the-sideof the machine and are connected by chainloops 127 so that adjustment ofthe hand Wheels 128 will adjust the screw shafts 127. The push rods 11%which actuate the folding plates have longitudinally adjustableconnections 129 to permit the proper positioning of the crank arms 116in all adjusted positions of the bearing brackets 115.

The bearing brackets 107 that support the top folding plates areslidably adjustable on the ways 1116 and are moved laterally by screwshafts 130. The shafts 1315 extend to the sides of the machine wherethey are connected by chain loops 131 for simultaneous adjustment of thebearing brackets on either side of the machine. The length of the pushrods 111 is adjustable by a telescopic section having a releasableclamping connection 132.

Reinforcing zigzag panel inserting station After the bottom panels havebeen formed to provide the spaced channel shaped legs as described theyare advanced by the conveyor chains 47 and 49 to the reinforming panelinserting station 41, the construction and operation of which is mostclearly shown in Figs. 7 to 16. Asappears most clearly in Fig. 9 thestation consists of a lower support for the chains 47 and 49 and for thebottom of the center legs 32. The support consists of suitablelongitudinally extending rails, center rail 133 having side walls 134.Side rails 135 laterally retain the sides of the laterally outer legs.The previously described rails 49 and 50 support the conveyor chains.Positioned immediately above the bottom panel supports are three foldingunits indicated generally at 136. The center folding unit is fixed overthe center leg of the panel and the side units are laterallyadjustable'by means of the screw shafts 137 to registerwith the sidelegs of the panels. Positioned vertically above the folding units is afeed and pressure head 1338 supported on a longitudinal beam 139 that isvertically reciprocal by a crank 141 connected by the suspension rods142 to the head. A push rod 143 actuates r the head as will bedescribed. The head includes structure for regulating the feed ofreinforcing panels to the several panel folding units as will bedescribed. Positioned above-the feed head 13% is a distributor conveyor144 and control gate 145 that coact with a stationary mag azine 146 todistribute a reinforcing panel to each section of the head 138.

Considering first the distributing conveyor 144 and the gate 145 andwith particular reference to Figs. 7, 8 and9. it'will be noted that themagazine 146 is supported in a fixed position along one side of themachine and is considerably longer than the length of the pallets toreceive and store long fiat blanks 361 from which the zig zagreinforcing panels 36 are formed. Laterally reciprocable feed shoes 147sliding between support rails and across the bottom of the magazine feedindividual blank strips 361 out of the magazine and into the path of thefeed dogs 149 on the transversely extending distributor conveyor chains144. The feed dogs 149 advance the, strip laterally across thesupporting strips of the gate 145. The gate is supported at its frontand rear ends by rollers 151 (see-Fig. 9) rollingin atransverse track152. The gate 145 is reciprocated by a push rod 153 connected to thecrank 154 and in turn actuated by a push rod 155. In its retractedposition towardthe right side of the machine as appears in Fig. 9, thesupporting strips of the gate approach the edges; of the support rails148 and prevent the panels 361 from falling down; wardly at this point.The reinforcing panels are thus conveyed across the supporting strips150 of the gate and if t?.e gate in retracted position will falldownwardly over ti left edge of the gate. The left edge of the gate isclosable in the advanced position of the gate against the ends of fixedsupport bars 156 so that reinforcing panels can be translated by theconveyor beyond; the

' The feed shoes 147 are actuated by link conlationship with the gate aswill be described.

The feed head 138 carries three longitudinally extending laterallyspaced feed chutes 159. Inclined guide rods 160 extending between thesides of the side guide chutes and the edges of the fixed support rails148 and 156 direct reinforcing panels that fall over the edges of thefixed plates into the side chutes 159. Other inclined bars 161 guidepanels that fall over the edge of the gate into the center feed chute.

Each of the inclined bars 160 and 161 carries a movable stop finger 162designed to intercept and support the reinforcing panels prior to entryinto the feed chutes. The fingers 16?. are swingably mounted andconnected to be actuated simultaneously by the electrically operatedsolenoids 163.

To accommodate the head 138 for adjustment along with the other portionsof the machines the side, feed chutes are slidably supported andadjustable laterally by screw shafts 164. The shafts 164', are connectedon each side of machine by chain loops 165.

After a reinforcing blank has been distributed to each of theintercepting fingers the solenoids 163 are actuated to drop thereinforcing blanks which are then distributed by the feed chutes 159 tothe folding units 136.

The construction and operation of the folding units 136 is most clearlyillustrated in Figs. 10 to 12. Each folding unit consists of side plates166, spaced apart by the same distance as the sidse of the pallet legpositioned therebelow, and laterally outer support bars 167. Each sideplate is held in fixed spaced relation to its associated support bar byspacers 166A. The ends of the Support bars 167 are adjustably supportedfrom transverse cross beams 168 of the framework of the machine. Atransverse shaft 169 extends transversely through both the inner sideplates 1'66 and the support bars 167 of all the folding units while stubshafts A project inwardly from the rear ends of the support bars of eachfolding unit. Transversely projecting seats 170 project from the innersides of the side plates 166 to intercept and support the edges of theflat reinforcing panels 361 as they are delivered to the folding unitsby the chutes 159. The lower edges of the chutes are slotted as at 170Ain Fig. 11 to clear the seats when the chutes are depressed.

Secured to the upper edges of the outer bars 167 are a plurality ofupright bearing brackets 171. The brackets 171 are staggered alongopposite sides of the folding unit and support pivot pins 172 aboutwhich the laterally outer ends of folding levers 173 are pivoted. Thefolding levers 173 project inwardly over the side plates 166 and havedepending vertical folding arms 174 on their inner ends. Each foldinglever 173 carries a depending tappet 175 that is movable laterallybetween the inner side plate 166 and the outer support bar 167.

The previously mentioned shafts 169 and 169A carry sprockets aroundwhich folding chains 176 are trained. The chains carry can. blocks 177that are selectively positioned and cammed to opposite sides of thechain as indicated at 178 in Fig. 10 to successively engagethe assessedtappets 175 and swing the folding arms 174 inwardly against the fiatreinforcing panel and across the space between the side plates 166 toform the flat panels into the zigzag panels as shown in Fig. 10.Adjustment of the bearing brackets 171 permits adjustment of the spacingof the folding arms and the length of the corrugations formed in thereinforcing panel.

The front edge of the fiat panel 361 is cammed rearwardly and the firstfold is formed therein against the transverse cam plate 701 andsucceeding zigzag folds are then formed in the panel thus shortening itto clear the rear seat 170. The forward seat 170 is located to laywithin a corrugation or fold and so no longer supports the panel. Therear edge of the panel is folded and snapped over a guide rib 702 andlocated above a vertical guide slot 703 so that when the foldedreinforcing panel 36 is pressed downwardly from between the side platesits ends are held against expansion and guided into the proper positionin the leg of the pallet positioned therebelow.

In order to prevent the newly folded zigzag reinforcing panel fromunfolding and expanding longitudinally from the ends of the legs of thepallet the side walls of the pallet legs are slit and bent inwardly inretaining ears 38 formed by structure appearing in Figs. 14 to 16. Atthe proper positions, the side rails 135 that support the pallet legsbelow the folding units are apertured as at 180 and guide plates 181 aresecured to the bottoms of the side plates to support air cylinders 182.The guide plates 181 guide upstanding arms 183 connected to the pistonsof the air cylinders. The arms 183 carry punch pins 184 that arereciprocated by the air cylinder through the apertures 180 to pierce theside walls of the pallet legs and fold the tabs 38 inwardly. Asillustrated the pins 184 are desirably provided with angled shoulders185 to form sharp bends at the bases of the tabs.

After the three reinforcing panels for each pallet have been folded intozigzag shape, the head 138 and its depending feed chutes 159 are loweredfrom the retracted position shown in Fig. 9 to an advanced positionshown in Fig. 12. The longitudinal extending lower edges of the chutes159 extend transversely of the upper edges of the reinforcing panelswhich are now zigzag in shape so that lowering of the feed chutespresses the zigzag reinforcing panels out of the folding units firmly tothe bottom of the hollow legs and between the ears 38. The head 138 isthen retracted or elevated and the pallet is ready to advance to the toppanel attaching station 43. Duringthe folding and inserting of thezigzag reinforcing panels, the distributing conveyor 44 and the gate 145have been operating to distribute an additional set of three flatreinforcing blanks to the intercepting fingers 162 so that the apparatusis ready to immediately commence a succeeding operation.

Top panel attaching station The folded bottom panels of the pallet withthe reinforcing zigzag panels in the legs are advanced by the conveyorchains to the top panel attaching station 43 where the center connectingportions 34 are firmly supported by strong support plates 186 (see Fig.17). In addition to the conveyor chains the bottoms of the legs of thepallet are firmly supported by plates 187. The marginal flanges of thebottom panel which have heretofor projected loosely from the bottompanel are drawn downwardly by deflecting plates 188 mounted on crankarms 189 at the ends of the station. In this position the top of thepartially completed pallet is clear to receive the top panel of thepallet. The top panel 37 is picked up by suction cups 190 carried by adelivery frame 191. The

frame 191 is movably supported at its front and rear ends by atransverse chain conveyor 192 which reciprocates the frame to alaterally disposed pick-up position as shown in Fig. 17 and advances thetop panel across a glue applying roll 193. A stop finger 194 engageableby the frame 191 actuates a limit switch 195 to stop outward motion ofthe pickup frame while a limit step 196 is h gaged by the right edge ofthe top panel to actuate the limit switch 197 and stop inward feedingmotion of the top panel and the delivery frame in proper position overthe partially completed pallet. The transverse feed conveyor chains 192are reversably driven by the motor 198 mounted on the side of themachine. Suitable switching controls not illustrated reversably actuatethe motor in timed relation with the other elements of the machine.

The limit stop 196 is pivotally supported at 199 on a supporting beam200 that is slidably adjustable in the bracket 201 at the side of themachine to permit adjustment for different widths of pallets. The switch197 carried by the limit stop 196 is urged against an adjustable stopscrew 202 by the spring 203.. In order to hold the switch 197 out ofcontact with the stop screw 202 and to prevent the limit stop 196 fromexerting a returning pressure on the top panel 37 after it is releasedby the suction cups 190, a lock lever 204 is pivoted on the bar 200 andweight biased to fall into blocking engagement with the lug 205 on thestop lever. The switch 197 is thus held in position to reversiblyenergize the motor 198 until the frame 191 is retracted and until thepressure head 206 is depressed as will be described. The

pressure head 206 carries a trip screw 207 that engages the inner end ofthe lock lever 204 to release the lock and permit the stop lever 196 toassume its operative position.

In order to permit retraction of the frame 191 and the suction cups tothe supply stack of top panels without contacting the glue roll 193 theentire conveyor 192 is carried on a cross frame 208 pivoted at the rightside of the machine at 209 and supported at the left side by suspensionlinks 210.

and 24. Longitudinally extending marginal support bars 213 extend alongthe sides of the pallet underneath the margin flanges and these bars aresupported in the center by the piston rods 214 of air cylinders 215. Attheir ends the bars 213 carry pivots 216 to which the inner ends of thecrank arms 189 are attached. As the bars 213 are elevated cam surfaces217 on the crank arms are brought into engagement with fixed pins 218 tocam the crank arms downwardly against the tension of springs 219 asappears in Fig. 21. This causes the hold down plates 188 to swinglaterally out of the way and permit the bars 213 to rise and clamp themarginal flanges 35 against the edges of the top panel 37 and in turnagainst the bottom plate 220 of the hold down head.

In order that the backing bars 213 and the air cylinders 215 by whichthey are operated may be moved laterally to accommodate pallets ofdifferent widths the cylinders 215 are supported between pairs oflongitudinally extending plates 221 connected at their outer ends toupright plates 222 that project upwardly through slots in the fixedbottom panel 223 and through slots in the slide plate 224 for attachmentto the under sides of flat slides 225 slidable on the slide plates 224.The upper portion of the air cylinder 215 is flattened and boltedbetween the plates 221 and has an upstanding journal portion 226 thatguides the piston rod 214-. The slide plates 224 which carry thesupports for the side legs of the bottom palletv and chain supports 50have depending ears 227 engaged

